This document relates to image cancellation in receivers.
Reception of a low-level radio-frequency (RF) signal often benefits from low noise and high precision operation. Noise and imprecision in such circuits have many different origins. Interference from another frequency band is a factor that can limit system performance.
One common undesired signal is an image frequency that is symmetrical to the signal frequency relative to the local oscillator frequency of a downconverter. Interference caused by the image frequency is referred to as image frequency interference. Image frequency interference can produce undesirable content in the eventual received signal, often called signal leakage or image leakage.